Technology Can Fortify Crops to Cope With Mother Nature

Did you know it takes 3,000 gal. of water to produce 1 bu. of corn? To help make sure that water is available and minimize weather’s impact on yield there are long- and short-term steps you can take.
( Darrell Smith )

Your father used to say, “Everybody talks about the weather, but nobody does anything about it.” That was then, and this is now. We still can’t change the weather, but using technology can fortify crops to better cope with whatever Mother Nature throws at you—and she’s throwing even more curveballs these days.

“Especially with today’s weather, farmers can no longer rely solely on preventive treatments or reacting after a weather disaster is upon them,” says Farm Journal Field Agronomist Ken Ferrie. There are numerous ways to weatherproof your crops, from hybrid selection through harvest, in wet, dry and normal seasons.

Let’s start with water. “Long-term water management practices include surface and subsurface drainage,” Ferrie says. “Once installed and managed, they last for years. Other practices, which often are specific to individual fields or management zones, must be done every year.”

Begin by examining yield maps and weather history. “If some fields or areas are excessively wet seven out of 10 years, you need to install drainage,” Ferrie says. “At the opposite end of the spectrum, if a lack of water causes crops to fail in seven out of 10 years, you need to think about installing irrigation. No short-term management practice will help if the crop is standing in water or if the soil can’t provide the 3,000 gal. of water needed to produce a bushel of corn.”

Long-term solutions are the most expensive to apply, so take plenty of time to figure out how to get the most bang for your buck. “With drainage, you want only to remove excess water, while retaining the rest for your crop,” Ferrie says. “Here’s where new technology can help. Today we can install controlled drainage systems, using gated tile to lower the water table to the depth we choose and when we choose to do it.”

Your system must relieve crops from saturated soil within 48 hours of a rainfall. “Managing drainage requires knowing where your water table is located,” Ferrie says. “You can do this relatively cheaply with inspection wells, made from PVC pipe extending below the tile line, or embedded sensors in the soil.”

The more time you spend designing your drainage system, the more efficient it will be, Ferrie adds. Maximizing efficiency benefits crop yield and reduces the amount of nutrients leaving your fields in drainage water.

Variable-rate technology (VRT) makes irrigation more efficient. “You don’t want irrigation water to run off and be wasted,” Ferrie says. “To use VRT, you need to know and monitor the infiltration rate and water-holding capacity of every soil management zone. You can do that by digging in the soil or burying moisture sensors. Sensors have the advantage of letting you monitor soil moisture remotely with your computer or smartphone.”

What if you don’t own the land that needs improvements? “You might offer to pay part of the cost of improvements in return for lower rent or a longer-term lease,” Ferrie says. “To protect both parties, hire an attorney to prepare the agreement.”

Now look at short-term water management practices. “With weatherproofing, the biggest water management issue I see is soil compaction,” Ferrie says. “Compacted layers cause soil to become saturated in rainy years, and a shortage of water when the weather turns dry, by restricting water movement up and down the soil profile.”

Knowing how and when to remove compaction, and keep it out, is the key. “I’ve seen farmers spend the fall tearing out compaction, only to put it back in the following spring,” Ferrie says. About 80% of the compacted layers Ferrie finds were put in during the first spring tillage pass. Another source of compaction is wheel tracks.

Working soil wet is a leading cause compaction. “Let your soil conditions, not the neighbors, tell you when to till,” Ferrie says. “With horizontal tillage, apply the ribbon test: In the wettest area of the field, dig 1" below where you run your sweeps. If you can ball up the soil in the palm of your hand and then make a 1" ribbon between your thumb and forefinger, doing tillage will put in compaction.”

In a vertical tillage system, the primary compaction concern is the wheel tracks. “Before you till, pause and ask yourself if the ground can support a tractor without causing compaction,” Ferrie says.

Once horizontal layers are removed, converting to vertical tillage will make it easier for water to move down to the tile line after a storm and back up to the surface when the crop needs it. “Farming vertically means using no-till, strip-till or vertical tillage tools rather than horizontal tillage,” Ferrie says. “You need to eliminate horizontal sweeps and disk blades.”

A basic step in water management involves getting soil into shape for planting. In a system that involves primary tillage, this process begins in the fall. “Your fall tillage tool needs to leave the surface level enough you enter spring with less than 3" peaks and valleys,” Ferrie says. “The tops of the peaks dry out in the spring, while the valleys stay moist. If the peaks are too tall, you fill the valleys with dry soil. It will take time for the moisture levels to even out.”

Patience is a weatherproofing tool. Possibly the worst situation that can arise is when a field has poor drainage and the operator lacks patience. “We often hear someone say he had to work the soil—cut it open and dry it out—to make it fit for planting,” Ferrie says. “What he’s really saying is, ‘I need to loosen the surface soil so water evaporates away, and put in a compacted layer to keep more water from moving up through the profile.’

“While working soil to dry it out lets you plant earlier, it backfires in July and August when you need water to percolate upward through the soil and crop roots to grow deep.”

The enemy of patience is peer pressure. Upon discovering stressed corn resulting from compaction caused by wet tillage, Ferrie is often told, “Everyone else was tilling, so I figured the soil must be dry enough.

“The first farmer’s fields might be drier because of better drainage. Or, he might have run a vertical tool that worked only the surface but created so much dust it looked like the soil was dry from a distance,” Ferrie says.

Examine your own fields—every management zone, not just a few areas close to the farmstead, he adds.

What if exhibiting patience, while neighbors are running hot and heavy, results in a phone call from your farm manager or landlord? “If you explain tillage was delayed because of poor drainage, it might help persuade the landowner to install tile,” Ferrie says.

“Once growers stop worrying what the neighbors think, they tend to move in the right direction in weather-proofing their water supply,” Ferrie says. “With tillage, knowing when to hold ’em and when to fold ’em requires discipline. Keep reminding yourself what you do in the spring will affect your crop all season.”